| /*------------------------------------- |
| * PNGFILE.C -- Image File Functions |
| *------------------------------------- |
| * |
| * Copyright 2000, Willem van Schaik. |
| * |
| * This code is released under the libpng license. |
| * For conditions of distribution and use, see the disclaimer |
| * and license in png.h |
| */ |
| |
| #include <windows.h> |
| #include <commdlg.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <zlib.h> |
| |
| #include "png.h" |
| #include "pngfile.h" |
| #include "cexcept.h" |
| |
| define_exception_type(const char *); |
| extern struct exception_context the_exception_context[1]; |
| struct exception_context the_exception_context[1]; |
| png_const_charp msg; |
| |
| static OPENFILENAME ofn; |
| |
| static png_structp png_ptr = NULL; |
| static png_infop info_ptr = NULL; |
| |
| |
| /* cexcept interface */ |
| |
| static void |
| png_cexcept_error(png_structp png_ptr, png_const_charp msg) |
| { |
| if(png_ptr) |
| ; |
| #ifdef PNG_CONSOLE_IO_SUPPORTED |
| fprintf(stderr, "libpng error: %s\n", msg); |
| #endif |
| { |
| Throw msg; |
| } |
| } |
| |
| /* Windows open-file functions */ |
| |
| void PngFileInitialize (HWND hwnd) |
| { |
| static TCHAR szFilter[] = TEXT ("PNG Files (*.PNG)\0*.png\0") |
| TEXT ("All Files (*.*)\0*.*\0\0"); |
| |
| ofn.lStructSize = sizeof (OPENFILENAME); |
| ofn.hwndOwner = hwnd; |
| ofn.hInstance = NULL; |
| ofn.lpstrFilter = szFilter; |
| ofn.lpstrCustomFilter = NULL; |
| ofn.nMaxCustFilter = 0; |
| ofn.nFilterIndex = 0; |
| ofn.lpstrFile = NULL; /* Set in Open and Close functions */ |
| ofn.nMaxFile = MAX_PATH; |
| ofn.lpstrFileTitle = NULL; /* Set in Open and Close functions */ |
| ofn.nMaxFileTitle = MAX_PATH; |
| ofn.lpstrInitialDir = NULL; |
| ofn.lpstrTitle = NULL; |
| ofn.Flags = 0; /* Set in Open and Close functions */ |
| ofn.nFileOffset = 0; |
| ofn.nFileExtension = 0; |
| ofn.lpstrDefExt = TEXT ("png"); |
| ofn.lCustData = 0; |
| ofn.lpfnHook = NULL; |
| ofn.lpTemplateName = NULL; |
| } |
| |
| BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) |
| { |
| ofn.hwndOwner = hwnd; |
| ofn.lpstrFile = pstrFileName; |
| ofn.lpstrFileTitle = pstrTitleName; |
| ofn.Flags = OFN_HIDEREADONLY; |
| |
| return GetOpenFileName (&ofn); |
| } |
| |
| BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) |
| { |
| ofn.hwndOwner = hwnd; |
| ofn.lpstrFile = pstrFileName; |
| ofn.lpstrFileTitle = pstrTitleName; |
| ofn.Flags = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT; |
| |
| return GetSaveFileName (&ofn); |
| } |
| |
| /* PNG image handler functions */ |
| |
| BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData, |
| int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor) |
| { |
| static FILE *pfFile; |
| png_byte pbSig[8]; |
| int iBitDepth; |
| int iColorType; |
| double dGamma; |
| png_color_16 *pBackground; |
| png_uint_32 ulChannels; |
| png_uint_32 ulRowBytes; |
| png_byte *pbImageData = *ppbImageData; |
| static png_byte **ppbRowPointers = NULL; |
| int i; |
| |
| /* open the PNG input file */ |
| |
| if (!pstrFileName) |
| { |
| *ppbImageData = pbImageData = NULL; |
| return FALSE; |
| } |
| |
| if (!(pfFile = fopen(pstrFileName, "rb"))) |
| { |
| *ppbImageData = pbImageData = NULL; |
| return FALSE; |
| } |
| |
| /* first check the eight byte PNG signature */ |
| |
| fread(pbSig, 1, 8, pfFile); |
| if (png_sig_cmp(pbSig, 0, 8)) |
| { |
| *ppbImageData = pbImageData = NULL; |
| return FALSE; |
| } |
| |
| /* create the two png(-info) structures */ |
| |
| png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, |
| (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL); |
| if (!png_ptr) |
| { |
| *ppbImageData = pbImageData = NULL; |
| return FALSE; |
| } |
| |
| info_ptr = png_create_info_struct(png_ptr); |
| if (!info_ptr) |
| { |
| png_destroy_read_struct(&png_ptr, NULL, NULL); |
| *ppbImageData = pbImageData = NULL; |
| return FALSE; |
| } |
| |
| Try |
| { |
| |
| /* initialize the png structure */ |
| |
| #ifdef PNG_STDIO_SUPPORTED |
| png_init_io(png_ptr, pfFile); |
| #else |
| png_set_read_fn(png_ptr, (png_voidp)pfFile, png_read_data); |
| #endif |
| |
| png_set_sig_bytes(png_ptr, 8); |
| |
| /* read all PNG info up to image data */ |
| |
| png_read_info(png_ptr, info_ptr); |
| |
| /* get width, height, bit-depth and color-type */ |
| |
| png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth, |
| &iColorType, NULL, NULL, NULL); |
| |
| /* expand images of all color-type and bit-depth to 3x8-bit RGB */ |
| /* let the library process alpha, transparency, background, etc. */ |
| |
| #ifdef PNG_READ_16_TO_8_SUPPORTED |
| if (iBitDepth == 16) |
| # ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED |
| png_set_scale_16(png_ptr); |
| # else |
| png_set_strip_16(png_ptr); |
| # endif |
| #endif |
| if (iColorType == PNG_COLOR_TYPE_PALETTE) |
| png_set_expand(png_ptr); |
| if (iBitDepth < 8) |
| png_set_expand(png_ptr); |
| if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) |
| png_set_expand(png_ptr); |
| if (iColorType == PNG_COLOR_TYPE_GRAY || |
| iColorType == PNG_COLOR_TYPE_GRAY_ALPHA) |
| png_set_gray_to_rgb(png_ptr); |
| |
| /* set the background color to draw transparent and alpha images over */ |
| if (png_get_bKGD(png_ptr, info_ptr, &pBackground)) |
| { |
| png_set_background(png_ptr, pBackground, PNG_BACKGROUND_GAMMA_FILE, 1, 1.0); |
| pBkgColor->red = (byte) pBackground->red; |
| pBkgColor->green = (byte) pBackground->green; |
| pBkgColor->blue = (byte) pBackground->blue; |
| } |
| else |
| { |
| pBkgColor = NULL; |
| } |
| |
| /* if required set gamma conversion */ |
| if (png_get_gAMA(png_ptr, info_ptr, &dGamma)) |
| png_set_gamma(png_ptr, (double) 2.2, dGamma); |
| |
| /* after the transformations are registered, update info_ptr data */ |
| |
| png_read_update_info(png_ptr, info_ptr); |
| |
| /* get again width, height and the new bit-depth and color-type */ |
| |
| png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth, |
| &iColorType, NULL, NULL, NULL); |
| |
| |
| /* row_bytes is the width x number of channels */ |
| |
| ulRowBytes = png_get_rowbytes(png_ptr, info_ptr); |
| ulChannels = png_get_channels(png_ptr, info_ptr); |
| |
| *piChannels = ulChannels; |
| |
| /* now we can allocate memory to store the image */ |
| |
| if (pbImageData) |
| { |
| free (pbImageData); |
| pbImageData = NULL; |
| } |
| if ((pbImageData = (png_byte *) malloc(ulRowBytes * (*piHeight) |
| * sizeof(png_byte))) == NULL) |
| { |
| png_error(png_ptr, "Visual PNG: out of memory"); |
| } |
| *ppbImageData = pbImageData; |
| |
| /* and allocate memory for an array of row-pointers */ |
| |
| if ((ppbRowPointers = (png_bytepp) malloc((*piHeight) |
| * sizeof(png_bytep))) == NULL) |
| { |
| png_error(png_ptr, "Visual PNG: out of memory"); |
| } |
| |
| /* set the individual row-pointers to point at the correct offsets */ |
| |
| for (i = 0; i < (*piHeight); i++) |
| ppbRowPointers[i] = pbImageData + i * ulRowBytes; |
| |
| /* now we can go ahead and just read the whole image */ |
| |
| png_read_image(png_ptr, ppbRowPointers); |
| |
| /* read the additional chunks in the PNG file (not really needed) */ |
| |
| png_read_end(png_ptr, NULL); |
| |
| /* and we're done */ |
| |
| free (ppbRowPointers); |
| ppbRowPointers = NULL; |
| |
| /* yepp, done */ |
| } |
| |
| Catch (msg) |
| { |
| png_destroy_read_struct(&png_ptr, &info_ptr, NULL); |
| |
| *ppbImageData = pbImageData = NULL; |
| |
| if(ppbRowPointers) |
| free (ppbRowPointers); |
| |
| fclose(pfFile); |
| |
| return FALSE; |
| } |
| |
| fclose (pfFile); |
| |
| return TRUE; |
| } |
| |
| |
| BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData, |
| int iWidth, int iHeight, png_color bkgColor) |
| { |
| const int ciBitDepth = 8; |
| const int ciChannels = 3; |
| |
| static FILE *pfFile; |
| png_uint_32 ulRowBytes; |
| static png_byte **ppbRowPointers = NULL; |
| int i; |
| |
| /* open the PNG output file */ |
| |
| if (!pstrFileName) |
| return FALSE; |
| |
| if (!(pfFile = fopen(pstrFileName, "wb"))) |
| return FALSE; |
| |
| /* prepare the standard PNG structures */ |
| |
| png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, |
| (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL); |
| if (!png_ptr) |
| { |
| fclose(pfFile); |
| return FALSE; |
| } |
| |
| info_ptr = png_create_info_struct(png_ptr); |
| if (!info_ptr) { |
| fclose(pfFile); |
| png_destroy_write_struct(&png_ptr, (png_infopp) NULL); |
| return FALSE; |
| } |
| |
| Try |
| { |
| /* initialize the png structure */ |
| |
| #ifdef PNG_STDIO_SUPPORTED |
| png_init_io(png_ptr, pfFile); |
| #else |
| png_set_write_fn(png_ptr, (png_voidp)pfFile, png_write_data, png_flush); |
| #endif |
| |
| /* we're going to write a very simple 3x8-bit RGB image */ |
| |
| png_set_IHDR(png_ptr, info_ptr, iWidth, iHeight, ciBitDepth, |
| PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, |
| PNG_FILTER_TYPE_BASE); |
| |
| /* write the file header information */ |
| |
| png_write_info(png_ptr, info_ptr); |
| |
| /* swap the BGR pixels in the DiData structure to RGB */ |
| |
| png_set_bgr(png_ptr); |
| |
| /* row_bytes is the width x number of channels */ |
| |
| ulRowBytes = iWidth * ciChannels; |
| |
| /* we can allocate memory for an array of row-pointers */ |
| |
| if ((ppbRowPointers = (png_bytepp) malloc(iHeight * sizeof(png_bytep))) == NULL) |
| Throw "Visualpng: Out of memory"; |
| |
| /* set the individual row-pointers to point at the correct offsets */ |
| |
| for (i = 0; i < iHeight; i++) |
| ppbRowPointers[i] = pDiData + i * (((ulRowBytes + 3) >> 2) << 2); |
| |
| /* write out the entire image data in one call */ |
| |
| png_write_image (png_ptr, ppbRowPointers); |
| |
| /* write the additional chunks to the PNG file (not really needed) */ |
| |
| png_write_end(png_ptr, info_ptr); |
| |
| /* and we're done */ |
| |
| free (ppbRowPointers); |
| ppbRowPointers = NULL; |
| |
| /* clean up after the write, and free any memory allocated */ |
| |
| png_destroy_write_struct(&png_ptr, (png_infopp) NULL); |
| |
| /* yepp, done */ |
| } |
| |
| Catch (msg) |
| { |
| png_destroy_write_struct(&png_ptr, (png_infopp) NULL); |
| |
| if(ppbRowPointers) |
| free (ppbRowPointers); |
| |
| fclose(pfFile); |
| |
| return FALSE; |
| } |
| |
| fclose (pfFile); |
| |
| return TRUE; |
| } |
| |
| #ifndef PNG_STDIO_SUPPORTED |
| |
| static void |
| png_read_data(png_structp png_ptr, png_bytep data, png_size_t length) |
| { |
| png_size_t check; |
| |
| /* fread() returns 0 on error, so it is OK to store this in a png_size_t |
| * instead of an int, which is what fread() actually returns. |
| */ |
| check = (png_size_t)fread(data, (png_size_t)1, length, |
| (FILE *)png_ptr->io_ptr); |
| |
| if (check != length) |
| { |
| png_error(png_ptr, "Read Error"); |
| } |
| } |
| |
| static void |
| png_write_data(png_structp png_ptr, png_bytep data, png_size_t length) |
| { |
| png_uint_32 check; |
| |
| check = fwrite(data, 1, length, (FILE *)(png_ptr->io_ptr)); |
| if (check != length) |
| { |
| png_error(png_ptr, "Write Error"); |
| } |
| } |
| |
| static void |
| png_flush(png_structp png_ptr) |
| { |
| FILE *io_ptr; |
| io_ptr = (FILE *)CVT_PTR((png_ptr->io_ptr)); |
| if (io_ptr != NULL) |
| fflush(io_ptr); |
| } |
| |
| #endif |
| |
| /*----------------- |
| * end of source |
| *----------------- |
| */ |